If you're asking for snippets of Pro_News code to be executed when another module is executing, then as far as I know the only way is through blocks. Only 1 module runs at a time. Hence my solution above.
If Pro_News was the executing module (not "the original Content module") then more options might evolve. But the straightforward approach would most likely still want to operate via blocks. But Pro_News blocks use callbacks to Pro_News itself so they could use context somewhat - but remember that blocks are prepped for display before the module output is sent, so there is a limitation there.
Creating your "snippets" when Pro_News is the module would just (!?!) mean additional output to the template system and more additions to the template, but I'd need a much clear understanding of the exact feature set to divine a real solution.
Yes to both of your last questions, but unless the money is significant, it also makes a difference if I feel that I can use it commercially to make my own sites better - because donations and fees for templates are important to cover my annual operating costs to provide this module to everyone, but to date they have not generated funds of even a $1/hr
But I'm not precluding anything at this point. Have you seen the fund raiser/kickstart style output that I have an image of
here? The significant point is that there is no code additions to the Pro_News module, it's all done in the template! Even allows individual to input their pledges and keeps a running account of the actual donations (through Treasury).